2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/82515A new method for studying the many-body response functions is elaborated and first applied to the $^3$He longitudinal response. An integral transform of the response function is calculated from the bound-state-type equations for several versions of the N-N force. The equations are solved with the help of the hyperspherical expansion. The final-state interaction is completely taken into account. The results are compared with the integral transform of the experimental response function for 250 MeV/c$\leq q \leq 500$ MeV/c. The difference amounts to 20-25\% with the experimental response substantially exceeding the theoretical one in the low-energy region.7 pages, LATeX, 2 figures (postscript files), IAE-5600/2Nuclear Theorytext